Pressure from investors and consumers is prompting more and more corporations around the world to evaluate the impact their business is having on the environment and human rights and to report that impact.

Companies first started making environmental impact reports in the late 1980's, according to Alan White of the Global Reporting Initiative, which devises international standards for social reporting.

By the mid-1990's, Mr. White said, hundreds of companies were issuing impact reports. Then the public began clamoring for more information, and the Internet made details more accessible.

Today, he said, thousands of corporations issue social reports. "These are overwhelmingly voluntary actions. Companies want to be responsive, sensitive to what their stake holders are seeking, whether it is customers or investors," Mr. White said.

These social reports include information ranging from the amount of waste a company reuses to the wages it pays workers.

Here are some questions Mr. White said the Global Reporting Initiative asked General Motors to answer in its social report. "What is the average fuel efficiency of your vehicles? What are the numbers of employees in your various facilities? What is the total energy use in your factories? Do you conform to international labor standards with regard to freedom of association and child labor?" he said.

The London-based environmental group, Corporate Register, gathers data from the 5,000 biggest global companies and publishes it on its web site. Spokesman Paul Scott said, the web site attracts many visitors. "There is a great academic interest, but the biggest users of all are businesses - businesses trying to catch up with this and to make sure that they are not left behind in their own sectors," he said.

Critics contend this voluntary self-reporting enables businesses to highlight the good things they are doing and omit the bad.

Paul Scott said about 40 percent of the reports in Corporate Register's database have been independently verified. His goal is to increase that percentage and to increase reporting from the developing world. "To date, it has mainly been companies in the developed world who have produced these kinds of reports because their stake holders are more interested in this type of thing," he said.

Mr. Scott says more reports are coming in now from Southern Africa. He hopes this is part of a new trend.